3-O-Methylquercetin is a metabolite in flavone and flavonol biosynthesis. It is a naturally occurring compound present in various plants, and was shown to have potent anticancer-promoting, antioxidant, antiallergy, and antimicrobial activity, and showed strong anti-viral activity inhibition of tomato ringspot virus.
3-O-Methylquercetin significantly inhibits cyclic adenosine monophosphate- (cAMP-) and cyclic guanosine monophosphate- (cGMP-) phosphodiesterase activity. It possess anti-inflammatory, bronchodilating properties and used in treatment of asthma. It suppresses the total inflammatory cells, tumor necrosis factor-α (TNF-α) and attenuates the production of interleukins.